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Hey guys, I recently stumbled upon stirling engines and I’m completely fascinated by them. As someone who is pretty familiar with ICE’s and knows the ins and out to produce more power I got to thinking on how one could produce more power from an SE.

My understanding is that the “fuel” for an SE is a heated gas and how fast you can move that heated gas between the the displacement and power cylinders from temperature and pressure differentials would determine your power output. (Please correct me if I’m wrong)

So on that assumption, we need to increase not only the volume of air moved but also it’s temperature in the “hot cylinder” and drastically decrease its temperature in the cold cylinder. By creating higher margins in the the temperatures we can create drastic pressure differences allowing the gas to move faster or more “violently” creating more power.

So how can we accomplish this? Well in order to get more displacement we can use a dished piston giving us more cc volume in the cylinder. Secondly, implementing the use of a cam and a valve in order to maintain vacuum in the cylinder. Essentially the idea is that a secondary torch would produce enough heated exhaust to power a small turbo that feeds into the heated cylinder through the valve opening providing super heated compressed gas into the displacement cylinder.

Now for the cooling side. I suppose water jackets in the cylinder walls could help but what If there were also valves on this cylinder? Ideally two, one for injection and one for exhaust/evacuation. On the injection side a compressed cooled gas can be used such as C02 or Nitrous. Filling the cylinder, cooling it rapidly, and allowing the pressure differences to pull the hot gas from the other cylinder. As that hot gas is pulled to the power cylinder our exhaust valve is opening and creating a secondary vacuum allowing more air to move into the cold cylinder. I’d assume this would create very turbulent environment and increase power output and torque allowing for heavier loads to be utilized with this engine design.

This was all just “what If” brainstorm and I understand this would negate the simplicity factor of the SE design so please feel free to criticize and tell me where things wouldn’t work as my understanding of fluid mechanics isn’t vast so I may be over seeing some problems that would arise.

Curiosityprevails wrote: ↑Wed Dec 01, 2021 7:40 pm Hey guys, I recently stumbled upon stirling engines and I’m completely fascinated by them.

Welcome.

As someone who is pretty familiar with ICE’s and knows the ins and out to produce more power I got to thinking on how one could produce more power from an SE.

A worthwhile ambition.

My understanding is that the “fuel” for an SE is a heated gas and how fast you can move that heated gas between the the displacement and power cylinders from temperature and pressure differentials would determine your power output. (Please correct me if I’m wrong)

I don't think there is 100% cansensus on how Stirling engines operate. It's always interesting to see someone thinking outside the box.

So on that assumption, ...

If you could include a drawing, It might provide a clearer idea how all this would fit together.

If valves and such are involved, you need to be looking at some of the relatives to the Stirlings, such as the Manson Engine

Tom that’s pretty interesting that there’s no consensus despite how old the technology is.

Also, give me a day or two to get some downtime and I’ll draw up a diagram to better explain my thoughts.

MikeB wrote: ↑Thu Dec 02, 2021 9:37 am If valves and such are involved, you need to be looking at some of the relatives to the Stirlings, such as the Manson Engine

I’ll definitely check them out I haven’t heard of them but am interested to see their design. Thanks!

The Erickson cycle and Engine is also an interesting potential.

https://en.m.wikipedia.org/wiki/Ericsson_cycle

I've thought of having an electric compressor fill a tank that feeds the engine. Generate electricity. Feed that to the compressor.

I've thought of having an electric compressor fill a tank that feeds the engine. Generate electricity. Feed that to the compressor.
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Thanks for the link!

In my search to find a cold compressed gas I ran across vortex tubes. I had never heard of them before but they may be perfect to implement in my design. Compressed air goes in and through the vortex hot air is put out through one side and cold air is put out through the other. The wiki says the temps can get to -50F on the cold side and up to 300F on the hot side. This is would help provide a huge temperature differential between the two cylinders and could possibly achieve what I originally posted. On top of that it make the system less complicated since it would require less valves and mechanisms than my original plan.